为了研究矩形钢管混凝土框架的抗震性能和塑性铰长度,对四榀由方钢管混凝土柱一矩形钢管混凝土梁组成的单层单跨钢管混凝土框架结构进行了拟静力试验研究和非线性有限元分析,得到了该类框架的破坏模式、框架梁柱塑性铰的长度范围及其发生规律。研究结果表明:所有矩形钢管混凝土框架均表现出“强柱弱梁”的破坏机制,滞回曲线为较饱满的梭形,具有良好的延性性能;梁、柱端塑性铰中心出现在距离环板和加劲肋h/4~h/2的位置,塑性铰长度约为100mm。对试验研究、理论分析和数值模拟得到的塑性铰长度进行了对比,结果吻合较好,说明选用的塑性铰长度计算方法适用于矩形钢管混凝土框架。
In order to study the seismic performance and plastic hinge length of concrete-filled rectangular steel tube frames, quasi-static tests and nonlinear finite element analysis of four single layer and span concrete-filled rectangular steel tube frames, which were composed of square concrete-filled steel tube columns and rectangular concrete-filled steel beams, were performed. The failure pattern, the length scope and occurrence regularity of beam-column plastic hinge were gotten. The results show that the failure mechanism of all concrete-filled rectangular steel tube frames are "strong column weak beam", and have plump hysteresis loops with better ductility; the center of beam's and column's plastic hinge appears in the position of h/4 h/2 at the end of the ring plate and the stiffener, plastic hinge length is about lOOmm. The results of the plastic hinge length that calculated by the tests, theoretical analysis and numerical simulation are similar. It shows that selection calculation method of plastic hinge length is suitable for the concrete-filled rectangular steel tube frame.